Can someone please help me fix this script?

if exist $filename remove $filename

[hisac]

<?
$filename= '/home/www/myip/remote-ip.html';

if exist $filename {
unlink($filename);
}

$newip = "<a href=http://$REMOTE_ADDR>$REMOTE_ADDR</a>";

$fp = fopen("$filename","w");

fputs($fp,$newip);

?>

Thank you very much.

[ergophobe]

if (file_exists($filename)) {
unlink($filename);
}